The Blender animation system cannot easily load animations from
one bone set to another. So I save all animations for a pet into one
Blender file to compensate.

I use Markers in the timeline to separate the animation: Markers are
the yellow triangles (at 400) and the triangle at 425. You can right click
a marker, and then G grab it to move it around. Markers are very useful in
the Dope Sheet for selecting a set of keyframes to move them around, too.

Document your animations:

I make a text file to explain to myself what each animation market set is and
what file name I saved it to. It is a lot easier to go back later and
tweak the animation.

A sample looks like this:

Marker 0 - 60
Name: TigerGrowl1.anim
Tiger growling with head and foot move - is a .anim file so mouth can move. Used in Gestures